1. Field of the Invention
The present invention relates to an optical transceiver, in particular, relates to a new structure of the transceiver that prevents the EMI noise from leaking outward.
2. Related Prior Art
The EMI standard, which is a world wide based standard to restrict the electromagnetic radiation from the electronic components and the electronic wirings, is ruled for the electronic equipments. The optical transceiver, which is one type of the electronics equipments including an optical portion and an electrical portion, may follow this standard by covering the electronic portion with a metal cover, which is similar to the EMI shielding of the electronic equipment.
The United States patent, U.S. Pat. No. 6,200,041, has disclosed an optical transceiver that includes a metal plate inserted between the flange of the optical subassembly and the receptacle to prevent the EMI noise from leaking out of the transceiver. In other prior arts, it has been known to prevent the EMI radiation from leaking out that the package of the subassemblies may be made of metal or in the case that they are made of resin with the metal coating on whole surface thereof comes in contact to the metal housing of the transceiver.
The optical receptacle is necessary to widely open to the outside in order to mate with the optical connector. Accordingly, when a gap exists between the optical receptacle and the optical subassembly, namely, the transmitting optical subassembly (TOSA) and the receiving optical subassembly (ROSA), installed in the rear side with respect to the optical receptacle, the EMI radiation may leak from the transceiver via this gap and the opening in the optical receptacle even when the electronic portion thereof is shielded by the metal housing.
The present invention has a feature to prevent the EMI radiation from leaking out from the transceiver by a new arrangement between the receptacle and the TOSA and the ROSA, in which the gap possibly induced between these two members may be effectively filled and the TOSA and the ROSA may be securely held by the receptacle.